Heretofore, various anti-collision measures or techniques have been proposed for body floor structures of vehicles, particularly automotive vehicles. For example, vehicles are known in which a cross member is additionally provided in a floor tunnel in order to minimize or suppress deformation of the vehicle at the time of a lateral or side collision. Also known is a vehicle body floor structure constructed to disperse a load, produced by a lateral collision, across the entire vehicle using a seat structure. Examples of such a vehicle body floor structure are disclosed in Japanese Patent Application Laid-Open Publication No. H09-136575 (hereinafter referred to as “patent literature 1”) and Japanese Patent Application Laid-Open Publication No. 2005-67427 (hereinafter referred to as “patent literature 2”), where a load applied from a side of the vehicle body is transmitted into a center console or transmitted to the upper surface of the floor tunnel.
In the vehicle body floor structure disclosed in patent literature 1, two hollow beams span between opposed side walls of the center console and are located at positions corresponding to the backs of front seats, so that a load applied from a side of the vehicle body can be transmitted into the center console.
In the vehicle body floor structure disclosed in patent literature 2, left and right side sills are provided on left and right sides of the vehicle body and extend in a front-rear direction of the vehicle body, and a floor tunnel provided on a laterally central portion of the vehicle body and extends in parallel to the left and right side sills. Further, left and right seats are disposed with the floor tunnel interposed therebetween, and a left cross member is provided under the left seat and connecting between the left side sill and the floor tunnel while a right cross member is provided under the right seat and connecting between the right side sill and the floor tunnel.
FIG. 5 hereof shows a conventionally-known vehicle body floor structure 200, in which a tunnel cross member 202 is provided within a floor tunnel 201 so as to minimize deformation of the vehicle body due to a load transmitted from a side sill 203 to the floor tunnel 201 via a seat cross member 204. Further, a load produced by a side collision can be dispersed across the entire vehicle body using the construction of the seat 205.
Environment-friendly vehicles have come to the front in recent years, but these vehicles are more complicated in structure than ordinary vehicles. Further, equipment mounted on the environment-friendly vehicles tends to be great in size.
Thus, in another conventionally-known vehicle body floor structure 210 shown in FIG. 6, a functional component 212 is sometimes mounted within a floor tunnel 211. Among examples of the functional component 212 are a high-voltage electrical system for a hybrid vehicle, a fuel tank of an internal combustion engine, a battery of an electric vehicle, etc. The functional component 212 is supported in the floor tunnel 211 by means of a sub chassis 213. However, in the case where the functional component 212 is mounted within the floor tunnel 211, a load caused by a side collision (i.e., side collision load) must be prevented from being transmitted to the floor tunnel 211, with a view to protecting the functional component 212 from the side collision load.
Thus, in still another conventionally-known vehicle body floor structure 220 shown in FIG. 7, a functional component 222 is constructed to have a relatively great strength and mounted on a sub chassis 223 that is in turn fixed to a floor tunnel 221. Thus, a load caused by a side collision can be safely transmitted to the floor tunnel 221. However, in this case, the functional component 222 itself tends to be great in weight, which would lead to an increased overall weight of the vehicle body.
Thus, in still another conventionally-known vehicle body floor structure 230 shown in FIG. 8, functional components 232 are fixed to a partition wall 234 without being constructed to have a particularly great strength, and these functional components 232 and partition wall 234 are mounted on a sub chassis 233 that is in turn fixed to a floor tunnel 231. However, when a load has been applied from a side of the vehicle body, the functional components 232 fixed to the partition wall 234 may also be undesirably dragged so that there would occur a possibility of the functions of the components 232 being impaired.
Namely, even in the case where a functional component is disposed within the floor tunnel provided on a laterally central portion of the vehicle body, it is desirable that arrangements be made for dispersedly transmitting a load caused by a side collision of the vehicle and preventing the collision load from acting on the functional component provided within the floor tunnel.